Industrial high temperature heat pump for simultaneous production of ice-water and process-heat

Industrial processes like dairy production, brewing etc. often require simultaneous cooling and heating. High temperature heat pumps (HTHP) with natural working fluids offer a cost-, energy efficient and sustainable solution. However, availability and performance data and components for HTHP are rare, which is addressed in this work. Here, the performance of a newly developed industrial scale propane-butane cascade HTHP is presented. It has a new developed semi-hermetic compressor, able to operate at high temperatures. The HTHP is installed in a Norwegian dairy and can lift from typical ice-water temperatures at 0.5°C to process hot-water at 112°C. Temperature glides are 4 K and 15 K at source and sink, respectively. Combined heating and cooling COP is 3.0 to 4.0 with a mean at 3.4 were measured. For this condition a temperature lift between heat sink and source was 88 K to 108 K. The highest temperature lift recorded between evaporation and condensation was 125 K. Condenser and evaporator capacities are within a range of 80 kW to 282 kW and 35 kW bis 134 kW, respectively. The cascade HTHP enables to utilizes waste heat form e.g. chilled/ice-water or dry-coolers effectively to supply process heat at 112°C. The HTHP is suited for a both retrofit and new installations reducing energy consumption by up to 64% and CO2-emissions by up to 94%.